Explore and characterize the antigens of normal, pre-malignant, and malignant human cells of types that are currently evaluated by manual cytologic techniques for the presence of pre-malignant and malignant changes. Qualitative and/or quantitative antigenic changes in pre-malignant and malignant cells which would allow discrimination from normal cells will be identified and characterized. The specificity and sensitivity of these changes will be evaluated with promising antigens. Assays should then be developed for application to human clinical cytology specimens.